The answer to 'average cost of roof decking' is that the cost can vary significantly depending on factors like the size of your roof, the type of decking material used, and your location. In general, you can expect to pay anywhere from $2 to $7 per square foot for roof decking materials and installation. The type of decking you choose, such as plywood, OSB, or tongue-and-groove boards, will impact the overall cost.
It's important to get quotes from local roofing contractors to get an accurate estimate for your specific project. They can assess the condition of your existing roof and provide a detailed breakdown of the materials and labor required. Keep in mind that the cost may also be affected by any necessary repairs or replacements to the underlying roof structure.